The present invention relates to a dual flush-volume valve assembly for a toilet tank. More particularly, the invention provides a modular dual flush-volume valve assembly for a toilet tank that may be installed as either, or converted between, a single flush-volume system and a double flush-volume system.
In the past, most toilets manufactured in the U.S. discharged approximately 3-5 gallons of water per flush. More recently, however, concerns with water conservation, combined with federal law requiring new toilets to have a maximum discharge volume of 1.6 gallons per flush, have led to the development of new water-conserving toilet systems and various devices for reducing the water consumption of older toilets.
One example of a device used to increase the efficiency of older toilets is a dual flush-volume toilet tank outflow valve assembly. Dual flush valve assemblies utilize separate flush valves that discharge different amounts of water for flushing solid and liquid waste. In one type of dual flush-volume valve assembly, a high-volume flush valve is positioned near the bottom of the toilet tank to pass a higher volume of water for flushing solid waste, and a low-volume flush valve is positioned higher in the toilet tank for passing a lower volume of water for flushing liquid waste. Thus, a user may select a high-volume flush when clogging presents a problem, and otherwise use a low-volume flush.
While known dual flush-volume valve assemblies do offer improved water conservation relative to older, high-volume toilet systems, they also have several shortcomings. For example, known dual flush-volume valve assemblies permit little, if any, adjustment of the relative volumes of the low-volume flush and the high-volume flush. This can pose a problem in retrofitting older toilet tanks, as the volume of water passed from the toilet tank during a low-volume flush may be dependent upon the shape of the toilet tank. As an example, when using a dual valve assembly of a selected height, more water may be discharged by the low-volume valve from a taller tank than from a shorter tank, as the level of water in the shorter tank may be closer to the low-volume valve than in the taller tank. This may cause problems with flushing, as an inadequate amount of water to flush waste from the toilet bowl may be discharged if the maximum water level in the toilet tank is too close to the low-volume valve.
Furthermore, the conversion of a single flush-volume valve system to known dual flush-volume valve systems may pose various difficulties. These difficulties may cause many consumers to avoid converting a single-volume flush system to a dual flush system, even given the long-term cost advantages of using less water per flush. Likewise, some toilet tanks may not be suited for fitting with dual flush-volume valve systems, while others may not be suited for fitting with single flush-volume valve systems. For these reasons, manufacturers may have to manufacture, and stores may need to stock, both single-volume valve systems and double-volume valve systems, which may increase manufacturing and distribution expenses.
Some embodiments provide a modular outflow valve assembly for a toilet tank, including a lower outflow tube section configured to be mounted to a toilet tank to pass water out of the toilet tank, wherein the lower outflow tube section has a high-volume flush valve configured to flush a first, higher volume of water when opened; an upper outflow tube section having a low-volume flush valve configured to flush a second, lower volume of water out of the toilet tank when opened, wherein the lower outflow tube section is configured to receive attachment of the upper outflow tube section to form a dual flush-volume configuration; and an overflow tube section, wherein the lower outflow tube section is configured to receive attachment of the overflow tube section in place of the upper outflow tube section to form a single flush-volume configuration.